Hunted. Hounded. Haunted.

She is the most important person in the world. She is The Key.

Journalist Liv Adamsen has escaped from the highly secretive Citadel at the heart of the ancient city of Ruin and now lies in isolation, staring at hospital walls as blank as her memory. Despite her inability to recall her past, something strange is stirring within her. She feels possessed by a sensation she can't name and plagued by whispers only she can hear: "KuShiKaam", the key.

To others the meaning is clear. For a mercenary operating in the Syrian Desert, a man known only as "The Ghost", Liv may hold the key to one of history's most powerful secrets. For the brotherhood of monks in the Citadel - now cursed by a terrible plague - her return to Turkey may be the only way to ensure their survival. And for a powerful faction in Vatican City, her very existence threatens the success of a desperate plan to save the church from ruin.

At the center of events that defy explanation and hunted by someone she believes might be trying to kill her, Liv turns to the only person she can trust: a foundation worker named Gabriel Mann. Together they must elude capture and journey to the place where all life began.

From New York to Rome to the deserts of the Middle East, worlds collide in a race to uncover a revelation dating from the creation of man in this electrifying follow-up to the international best seller Sanctus.